Current formulations for household cleaners and other compositions have an added benefit of generating a gas when mixed with water, thereby increasing their cleaning ability. Typically, this off-gassing is inconsequential since water is not introduced into the formulation until after the cleaner is dispensed from the original package. However, many users rinse the inside of the container to get any residual product out for the final use. This is generally not a problem because most products do not produce a gas when contacted with water.
In the case of cleaning products that off-gas on contact with water, rinsing the interior of the container or attempting to thin the cleaner for additional usage by the user can be an issue. There is no significant problem as long as the product is rinsed out of the container and used immediately. However, the problem arises when the user fills the container with water to soak the residual product off the inner walls for an extended period of time or simply adds water to increase the amount of product in an effort to be more economical. In these cases, the closure is reattached to the container to prevent spilling. This reapplication of the closure presents the ultimate problem in that pressure is able to build over time in the resealed container resulting in the package bulging. When the user reopens the package, a rapid de-pressurization can occur, causing product to be expelled, potentially resulting in injury or at a minimum, significant mess.
To further compound the issue, many of the current attempts to solve this problem have been ineffective and often confuse the user. In systems where the container is intended to be opened for repeated use, the package would be rendered non-functional as the user would be able to add water to the container but not be able to reattach the closure. In this case, both the product and the package would be non-functional.
Other systems exist that prevent pressure from building within the container and allow the closure to be reattached. However, these systems also allow water to be introduced within the container and the package resealed. In these systems, the product is rendered virtually unusable although the package is functional. Therefore, the user is unaware that the product and package have not been used as intended, and more importantly, that the product has reacted with the water and become ineffective. When the user then tries to use the product, it will not perform as intended.
These existing solutions typically have one of two shortcomings: 1) the system utilizes a thread or snap feature that allows the package to be opened and resealed numerous times with little degradation to the thread or snap feature, or 2) the system incorporates a breakaway feature that destroys the engagement between the closure and bottle. These are most evident in tamper proof systems incorporating break bands or tear bands. Both systems convey immediate removal of the closure instead of removal at the end of life.
In addition, traditional venting systems are ineffective to handle the larger amounts of internal pressure generated by the off-gassing of the newer types of cleaning formulation. These systems prevent the internal build-up of pressure within the container without allowing the product to leak from the package. They also include delayed venting systems that incorporate a vent which is exposed when the user begins to open the package, thereby allowing pressure to release in a controlled manner as the package is being opened. However, these systems are only effective for small amounts of pressure build-up and also allow the water to be introduced into the package without any indication to the user that the product should be used immediately. Again, this results in the cleaning product reacting with the water and becoming unusable.
Therefore, what is needed is a non-resealable, snap-fitted container closure which enables the product to off-gas but which can not be resealed after removal.